feat(protocol): allow override of dial func

reach/client/protocol/protocol.go

@@ -3,12 +3,16 @@ package protocol
 import (
 	"context"
 	"log/slog"
+	"net"
 
 	"forge.cadoles.com/cadoles/go-emlid/reach/client/logger"
+	"github.com/pkg/errors"
 )
 
 type Identifier string
 
+type DialFunc func(network string, addr string) (net.Conn, error)
+
 type Protocol interface {
 	Identifier() Identifier
 	Available(ctx context.Context, addr string) (bool, error)
@@ -17,6 +21,16 @@ type Protocol interface {
 
 type ProtocolOptions struct {
 	Logger logger.Logger
+	Dial   DialFunc
+}
+
+var DefaultDialFunc = func(network, addr string) (net.Conn, error) {
+	conn, err := net.Dial(network, addr)
+	if err != nil {
+		return nil, errors.WithStack(err)
+	}
+
+	return conn, nil
 }
 
 type ProtocolFactory func(opts *ProtocolOptions) (Protocol, error)
@@ -40,3 +54,9 @@ func WithProtocolLogger(logger logger.Logger) ProtocolOptionFunc {
 		opts.Logger = logger
 	}
 }
+
+func WithProtocolDial(dial DialFunc) ProtocolOptionFunc {
+	return func(opts *ProtocolOptions) {
+		opts.Dial = dial
+	}
+}